SND / RTN is an interface module that can output a modular signal down to the line level and output it to the outside, and input the external line level and instrument level input sound to the modular level. A 1/4 inch jack is used for external connection.
From OUT, the signal to be sent and the signal to be returned are mixed by the DRY / WET control knob / CV and output. Ideal as an interface module that sends back to external effects.